login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A206479 Number of terms common to the binary expansions of m and n; a matrix by antidiagonals. 3
1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 2, 1, 2, 1, 2, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 2, 2, 2, 0, 1, 1, 1, 0, 1, 1, 0, 0, 2, 2, 0, 0, 1, 1, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,13

LINKS

Table of n, a(n) for n=1..99.

EXAMPLE

Northwest corner (the antidiagonals can be read either

southwest or northeast, since the matrix is symmetric):

1 0 1 0 1 0 1 0 1 0

0 1 1 0 0 1 1 0 0 1

1 1 2 0 1 1 2 0 1 1

0 0 0 1 1 1 1 0 0 0

1 0 1 1 2 1 2 0 1 0

0 1 1 1 1 2 2 0 0 1

1 1 2 1 2 2 3 0 1 1

...

11 = 1 + 1*2 + 1*8 and 29 = 1 + 1*4 + 1*8 + 1*16,

so that T(11,29)=2.

MATHEMATICA

d[n_] := IntegerDigits[n, 2];

t[n_] := Reverse[Array[d, 120][[n]]]

s[n_] := Position[t[n], 1]

t[m_, n_] := Length[Intersection[s[m], s[n]]]

TableForm[Table[t[m, n], {m, 1, 14},

  {n, 1, 14}]]  (* A206479 as a matrix *)

Flatten[Table[t[i, n + 1 - i], {n, 1, 14},

  {i, 1, n}]]   (* A206479 as a sequence *)

u = Table[t[n - 1, m], {n, 3, 16}, {m, 1, n - 2}];

TableForm[u]    (* A206566 as a triangle *)

Flatten[u]      (* A206566 as a sequence *)

v[n_] := Table[t[k, n + 1], {k, 1, n}]

Table[Count[v[n], 0], {n, 1, 100}]  (* A115478 *)

CROSSREFS

Cf. A206566, A115478.

Sequence in context: A118917 A325045 A204293 * A219484 A060396 A195470

Adjacent sequences:  A206476 A206477 A206478 * A206480 A206481 A206482

KEYWORD

nonn,tabl,base

AUTHOR

Clark Kimberling, Feb 09 2012

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 25 16:08 EDT 2019. Contains 322461 sequences. (Running on oeis4.)